Unequal varchar length of "tag" in nodereview and votingapi

Nodereview uses varchar(255) for its tag size, while votingapi limits the length of this field to varchar(64). That means that, since nodereview merges the values of votingapi & nodereview by this field in the nodereview_load function, no scores are retrieved for terms longer then 65 characters.

The attached patch fixes this (as long as the first 65 characters are unique for each term).